基于DSADC的旋变位置解码系统设计与研究

Research and Design of Resolver Decoding System Based on DSADC

传统电机旋变位置检测需专用解码芯片对信号解码,得到电机转子位置,或利用DSP产生激励信号,并设计相应调理电路,对返回信号调制滤波,得到包含转子位置信息的正余弦信号,再由DSP采样计算转子位置。DSADC(Δ-Σ模数转换)外设模块含有高频激励产生以及对高频信号采样、调制、滤波、积分等硬件功能,可在芯片内部实现旋变信号解码。分析了旋变的基本工作原理,利用TC275 DSADC产生旋变激励信号,并对旋变返回信号进行调制滤波,通过角度辨识算法解算出转子位置信号,并以旋变解码芯片解码结果为基准,对旋变解码系统功能进行验证,实验结果证明了该系统的正确性和实用性,避免了专用解码芯片的使用,可减少开发成本。

Traditional motor resolver position detection requires the dedicated decoder chip.It uses DSP to generate excitation signal,designs the conditioning circuit to modulate the return signal and obtain the cosine signal containing the rotor position,then calculates the rotor position.DSADC peripheral modules contain functions including high frequency excitation generation,signal sampling,modulation,filtering,integration and so on.The resolver decoding can be achieved within the chip.The operating principle of resolver was analyzed and TC275 DSADC was used to generate the excitation signal,modulate and filter the return signal.The rotor position signal was calculated by angle recognition algorithm.The result of decoder chip was used as benchmark to verify the function of designed decoding system.The experimental result proved the correctness and practicability of the decoding system which avoid the use of dedicated decoder chip and cut the cost.